The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Engine systems include an engine having an air intake manifold. Air flows into the intake manifold through an inlet. An air filter removes dirt or debris from the inlet air. A throttle valve regulates the air flow into the intake manifold. A controller determines an appropriate air/fuel (A/F) ratio for engine operation based on the air flow and other engine parameters. Internal combustion engines having one or more cylinders may be provided with at least one control valve for controlling the state of charge within the cylinder. The valve is located at or near the intake of the cylinder. The valve opens and closes to control the motion and velocity of the air entering the cylinder.
Typically a position sensor is mounted to the valve to indicate to the controller an actual position of the valve. The actual position is used by control systems to diagnose a malfunction of the valve. For example, the actual position and a commanded position may be compared to detect the malfunction. However, an indication of the position of the valve may not be sufficient to indicate the true status of the valve. Additional methods should be employed to ensure the valve is functioning during vehicle operation according to design requirements.